Decal

Placing decals in a level is a simple way to break up uninteresting textures, as well as bring together various level elements like brushes and terrain. A decal material has to be marked with the Decal flag in the Shader Generation Parameters in the material options, as shown below.

All materials located in the Materials/decals folder are correctly set up for use as decals. With the decal selected in the Perspective view, select a material in the Material Editor and click the Assign Material to Selection button.

The Decal consists of the following parameter options in the Properties tab:

Parameter

Description

Projection Type

Decals have 4 different projection types, numbered 0 to 3. To change a decal's projection, select the decal and change the value in the Projection Type drop-down menu.

Planar: The decal will be displayed in the exact same position in space as where you placed the center of the object. It is advised to only use this project type on flat surfaces, otherwise you may find the decal "floating" in the air. Planar projection offers the cheapest performance.

ProjectOnStaticObjects: The decal will be projected onto the geometry of an object in the level. It will be projected along the opposite direction of the blue Z axis. This method is automatically done as a deferred pass.

ProjectOnTerrain: The decal will be projected directly on to the terrain of your level, ignoring any assets that might otherwise receive the projection.

ProjectOnTerrainAndStaticObjects: This projection type is a combination of type 2 and 3, and will be displayed on both the terrain and objects. This method is automatically performed as a deferred pass.

Deferred

The deferred option is a new projection render type for Decals. When Enabled, it replaces the old Projection Type options "Project on Static Objects" and "Project on Terrain and Static Objects".

Deferred rendering is faster than the old rendering system but still slower than "Planar" Projection Type. That means keep as many Decals as possible in the "Planar" mode, especially if you plan a production for console release.

View Dist Ratio

Used for controlling the maximum viewing distance of the decal.

Sort Priority

This feature gives the user the control to decide in which order the decals are rendered in the engine.

Projection Depth

Allows the decal to be projected on every surface around it as long it stays in the specified projection depth.